Rete algorithm

The Rete algorithm stores not just exact matches but also partial matches this avoids reevaluating the complete set of facts when the rule base is changed. Additionally, it uses a decision-node-sharing technique, which eliminates certain redundancies. 

Pattern-matching algorithms are usually fast compared with complex statistical models or AI approaches. In particular, Rete and performance-improved variation Leaps recall previous matches and are quite efficient as long as no major changes occur in the input data sets. 

Forgy, C., Rete A Fast Algorithm for the Many Pattern/Many Object Pattern Match Problem, Artificial Intelligence, 19, 17, 1982. 

JBoss Rules is more correctly classified as a production rule system, which works with a memory of current states and details of a problem, a rule base, and an interpreter (i.e., inference engine), which applies the rules to each fact entering the memory. The system implements both Rete and leaps pattern-matching algorithms. Rules are stored in the production memory, and the facts that the inference engine matches against are stored in the working memory. A typical syntax is as follows ... 

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